Fine solids lodged in media
PSD, pressure difference, cloth construction and cake release influence depth loading.
Restore permeability by identifying the deposit
Disc Filter Cloth Blinding: Causes and Solutions
Diagnose cloth blinding from fine particles, reagents, scale or poor washing, then improve cloth selection, cleaning practice and operating conditions.
Permeability lossSymptom
Particles or scalePossible cause
Deposit + trendProof
Validated cleaningResponse
Safe diagnostic methodParticles Chemistry Washing
Identify What Is Blocking the Cloth
Blinding can be surface deposition, particles embedded in the structure, mineral scale, reagent film or a combination. Cleaning without identifying the deposit may damage media or move the problem.
Scale or reagent deposits
Water chemistry, pH, temperature and process reagents can form persistent resistance.
Poor coverage or unsuitable method
Blocked nozzles, wrong alignment, low flow or excessive force can reduce cleaning quality or damage cloth.
Safety before inspection or maintenance
Stop the equipment and isolate all hazardous energy that can cause rotation, vacuum, pressure, stored mechanical movement, electrical energization or chemical exposure. Follow the site lockout and permit procedure; inspection and maintenance must be performed only by authorized personnel.
Troubleshooting sequence1 2 3 4 5
Diagnose Deposit, Wash and Media Compatibility
Change one controlled variable at a time and retain the before-and-after operating evidence.
Trend performance
Confirm when permeability, flux or vacuum changed.
Inspect safely
Map deposit pattern, damage and wash coverage.
Review process
Check PSD, chemistry, water and reagent changes.
Test cleaning
Use an approved coupon or controlled method.
Prevent recurrence
Correct feed, wash, cloth selection or operating cause.
Evidence to record
Build a Trend, Not a Snapshot
Use the same instruments, sampling points and laboratory method so changes can be compared.
Cloth identityMaterial, construction, supplier/revision, installation date and position.
Deposit patternSurface, depth, scale, oil/reagent film and location across the disc.
Performance trendFlux, vacuum, filtrate, moisture and wash condition over time.
Feed and waterPSD, solids, pH, temperature, reagents and wash-water quality.
Cleaning historyMethod, frequency, pressure, chemistry and observed response.
DamageSeam, abrasion, stretching, puncture or sector-edge marks.
Corrective-action logic
Match the Response to the Confirmed Cause
Use BOYUN’s controlled media and cleaning instructions for the installed cloth and site chemical rules.
| Finding | Review | Possible controlled response |
|---|---|---|
| Loose surface solids | Wash coverage, nozzles, flow and timing. | Restore approved mechanical washing and correct alignment. |
| Embedded fines | PSD, cloth structure and formation conditions. | Test a more suitable media construction or upstream control. |
| Mineral scale | Deposit analysis and water/process chemistry. | Develop an approved cleaning and prevention plan. |
| Reagent or organic film | Process changes and chemical compatibility. | Confirm compatible cleaning with technical and site safety review. |
| Repeated localized blinding | Sector drainage, sealing, alignment and cake release. | Correct the mechanical or flow distribution cause. |
Continue the project path
Continue the Diagnostic Path
Use related technical and service pages to resolve the underlying cause.
Practical answers
Frequently Asked Questions
These answers support project preparation; the final recommendation depends on the actual duty.
Why is representative slurry data required?
Mineral names do not define filterability. Particle-size distribution, mineralogy, clay, reagents, solids and temperature can change cake formation, permeability and release. Use filterability testing when results matter commercially.
What should be sent for a preliminary review?
Provide dry-solids throughput, feed solids, particle-size data, target cake moisture, operating schedule, elevation and available utilities through the quote request.
Can BOYUN promise cake moisture from the mineral name alone?
No. A defensible target must be tied to representative feed data, test conditions, equipment scope and an agreed operating basis.
Define the Next Engineering Step
Share the feed, throughput, operating target and site constraints. BOYUN will identify missing information and recommend testing, sizing or the appropriate equipment scope.